Question
Using suitable identity, evaluate the following:
$999^2$
$999^2$
✓
Answer
$(999)^2=(1000-1)^2=(1000)^2-2 \times(1000) \times 1+1^2$
$=1000000-2000+1$
$=998001$
$=1000000-2000+1$
$=998001$
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